Interesting:
"... Although participants were instructed not to use the search to access
information or products, 61% used this method in Google ..."
What a surprise, on a site which is well-known precisely because it
provides a good search facility! This particular exercise seems to me to
defy common sense and what people actually do - what I would call poor
experimental design, unless they wanted to know if people would actually
follow counter-intuitive instructions in a usability test. Although I do
use breadcrumb navigation I don't think I have ever done so on Google, and
I would be surprised if anyone did. The other example they used seems much
more obvious as a test of breadcrumb navigation.
In their follow up study, a number of people made use of breadcrumbs:
"... Of the participants that were exposed to a site with a breadcrumb
trail (n=30), 40% used the breadcrumb five or more times to navigate on
the site (Range = 5 - 31, n=14). ..."
This would suggest that despite a number of problems (many sites are not
hierarchical, breadcrumbs are not always the intuitive way to get a task
done, ...) they are something that people find useful. The fact that
people who used them were not significantly faster or slower than those
who didn't suggests that different people find different approaches to
finding things obvious and comfortable. So it might be a good idea to
include different types of search mechanisms. (Now where have I heard that
before?)
There was some interesting work done by Inmaculada Fajardo Bravo and
others at the University of the Basque Country on how prelingually deaf
people search compared to others - it seems there might be important
differences in the way the two groups maintain information for searching.
(I have referred to this before, and a lot of the work is in Spanish,
although it was published in english for the Human Comuter Interaction
Conference in Crete in 2003, and is available as a PDF). I presume there
are other studies in this area, and would consider that the results on a
large scale are important for accessibility.
At the one end, David Poehlman says that as a blind user he finds
breadcrumb trails annoying. I find them helpful, although my mental model
of a site tends to be more weblike than the model of the site designer,
who often thinks there is a natural hierarchical structure. I really think
that usability studies that don't take disabled users into account, where
there is evidence that they may have different circumstances leading to
different results, can be bad for accessibility if we rely too heavily on
their results. (Knowing something is better than guessing. But a little
knowledge can be dangerous...)
Cheers
Chaals
On Wed, 04 Aug 2004 14:21:36 +0100, yeliz yesilada <yesilady@cs.man.ac.uk>
wrote:
>
> I think before we discuss how to represent breadcrumbs, we should first
> discuss whether they are useful or not. The following two URLs present
> results from a user evaluation which are quite interesting:
> http://psychology.wichita.edu/surl/usabilitynews/51/breadcrumb.htm
> http://psychology.wichita.edu/surl/usabilitynews/52/breadcrumb.htm
>
--
Charles McCathieNevile charles@sidar.org
FundaciÃ³n Sidar http://www.sidar.org